Preparation and Characterization of CdS and ZnS Particles in Nanophase Reactors Provided by Binary Liquids Adsorbed at Colloidal Silica Particles

Abstract

Determinations of adsorption excess isotherms of silica particle dispersions in ethanol−cyclohexane and in methanol−cyclohexane binary mixtures have established the formation of 0.5−5.0 nm thick alcohol rich adsorption layers at the silica particle interface. The adsorption layers on silica particles, formed in methanol−cyclohexane = 0.01:99.99 (mol/mol) and ethanol−cyclohexane = 0.05:99.95 (mol/mol), were used as nanophase reactors for the in situ generation of size-quantized CdS and ZnS particles. The semiconductor particles were generated by the addition of H2S to silica particle dispersions which contained different concentrations of Cd2+ or Zn2+. The smallest semiconductor particles were generated in dispersions which contained the least amount of precursors. Absorption spectrophotometry, small-angle X-ray scattering, rheological, and calorimetric measurements were used to characterize the dispersions. The presence of semiconductor particles increased the viscosities and decreased the immersion wetting enthalpies of the silica dispersions, indicating strong interparticle interactions.

Synthesis and characterization of ZnS-montmorillonite nanocomposites and their application for degrading eosin B

“…It has been reported that many metal [17][18][19] and metal compound (oxides, sulfides, etc.) [20][21][22][23] nanoparticles have been deposited on MMT with some nanoparticles intercalated into its interlayers. These MMT-based catalysts combined the functions of the nanoparticles and MMT together, and exhibited synergetic effects [24][25][26].…”

Macrocluster Formation of Alcohol on Silica Surface in Cyclohexane: Analysis of Interfacial Energy between Adsorption Layer and Bulk Solution

“…An interesting subject to study is the liquid adsorption onto solid-liquid interfaces from binary liquids, however, its study has been limited mainly to the adsorption isotherm measurement and its model analysis in spite of its basic and technological importance [17][18][19]. Recently, we have succeeded in identifying the structure of ethanol adsorbed on a silica surface in cyclohexane by employing the combination of surface forces measurement, adsorption excess isotherm measurement and infrared spectroscopy in the attenuated total reflection mode (ATR-FTIR) [20][21][22].…”

Cadmium Ion Adsorption Controls the Growth of CdS Nanoparticles on Layered Montmorillonite and Calumit Surfaces

“…The preparations, purifications, and characterizations of hexadecyl pyridium modified montmorrilonite, HDP-M, and sodium dodecylbenzenesulfonate modified calumit, DBS-C, have been described (5)(6)(7)(8). Ethanol and cyclohexane (p.a., Reanal, Hungary) were dried over 0.4 nm molecular sieves (Merck AG, Germany).…”

“…We have successfully employed ultrathin polar liquid layers, selectively adsorbed on solid surfaces in contact with alcohol-cyclohexane binary mixtures, as nanoreactors for the preparation of semiconductor particles (1,2). Specifically, we have generated CdS and ZnS nanoparticles in these nanoreactors at montmorrilonite clay platelet (5,6) and silica particle (7,8) surfaces.…”